Reverted to using 'include mpif.h' as the use of mpi.mod requires the MPI module be compiled with the same compiler as the DOUAR source, which is not true on geodyncomp

Added input of matrule to determine whether divFEM, majority or minority volume is used for material assignment in elements. Added input of bulkvisc to determine whether a penalty value or bulk viscosity is input. Added input of init_e2d to specify whether or not plastic materials should have their effective viscosity calculated using an initial strain rate.